Mix soy sauce, butter, brown sugar, salt, garlic powder, and black pepper together in a large bowl.
Wrap 1 piece of bacon around 3 or 4 green beans. Use a toothpick to secure in place, if necessary, and place in a baking dish. Continue with remaining bacon and green beans. Pour brown sugar sauce on top, cover the baking dish with aluminum foil, and refrigerate 8 hours to overnight.
Preheat the oven to 350 degrees F (175 degrees C).
Uncover baking dish; turn and dip the wrapped green beans so they are covered in the sauce.
Bake in the preheated oven until bacon is fully cooked, 45 minutes to 1 hour.